1. Field of the Invention
This invention relates to connectors in general, and more particularly to connectors of the type having a terminal retaining member for retaining terminals in terminal receiving chambers.
2. Related Art
Generally, connectors retain a terminal in a terminal receiving chamber by engaging a stamped piece portion, formed on the terminal, with a bottom wall of the terminal receiving chamber of a connector housing. Alternatively, the terminal is retained by engaging an elastic retaining arm, formed integrally with a top surface of the terminal receiving chamber, with a shoulder of an electrical contact portion of the terminal or a hole formed therein. However, these connectors are not without shortcomings. In particular, the stamped piece portion and the retaining arm are small and delicate. Therefore, they are easily damaged when male and female connectors are repeatedly connected together and disconnected from each other, As a result, the terminal may inadvertently withdrawn from the terminal receiving chamber, thereby defeating an electrical contact therebetween.
Therefore, a construction is disclosed in Japanese Patent Examined Publication No. 4-23391, in which a through hole, communicating with terminal receiving chambers, is formed in a central portion of an outer peripheral wall of a housing. A terminal retaining member is inserted through the through hole in a direction perpendicular to the axes of terminals, and is located at one end portion of each of the terminals. Side surfaces of plate-like projections of the terminal retaining member are engaged respectively with the terminals, thereby providing a second means for retaining the terminals.
FIGS. 15(A) and 15(B) show such a double-retaining connector. FIG. 15(A) is a cross-sectional view before the second retaining feature is effected, and FIG. 15(B) is a cross-sectional view after the second retaining feature is effected. Reference numeral 50 denotes a connector housing, and reference numeral 51 denotes a terminal receiving chamber. An elastic retaining arm 52 is formed integrally in each terminal receiving chamber 51, and engages a shoulder at a rear end of an electrical contact portion of a terminal (not shown), thereby providing a first means to retain the terminal.
A terminal retaining member 53 inserts into a through hole 55, which is provided in an outer peripheral wall of the housing 50, and communicates with the terminal receiving chambers 51, in a direction perpendicular to the terminals, and projections 54 of the terminal retaining member 53 are retainingly engaged respectively in retaining grooves formed respectively in the terminals (not shown).
In FIG. 15(A), the terminal retaining member 53 is located at a lower position, and therefore the retaining projections 54 are also located at respective lower positions, so that the terminals can be inserted respectively into the terminal receiving chambers 51. Once the terminal is inserted into the terminal receiving chamber 51, the elastic retaining arm 52 engages the shoulder of the terminal, thereby effecting the first retaining means. Then, when the terminal retaining member 53 is pushed up, the retaining projections 54 are moved upward, and are engaged respectively with retaining portions of the terminals, respectively, thereby effecting the second retaining means, as shown in FIG. 15(B).
Such double retaining connectors are generally thought to be acceptable, however they too have associated shortcomings. In particular, the terminal retaining member 53 is moved in a direction perpendicular to the terminals. Therefore, the displacement (i.e., stroke) of the terminal retaining member 53 is very short. Moreover, the proper actuation of the second retaining means is determined by visually confirming whether or not the terminal retaining member 53 is projected from the housing 50. Since the projecting amount is very small, it is difficult to make a judgment at a glance. Further, incorrect judgements are likely in which the second retaining means is inadvertently left inoperative.
It is an object of this invention to provide a connector in which determining whether or not terminals are properly retained by a terminal retaining member can be easily judged from the outside.